1. Technical Field
The present invention generally relates to a patch for mounting an electronic monitoring device to the inside surface of a pneumatic tire. More particularly, the present invention relates to a patch having an electronic monitoring device encapsulated directly to the patch to form an assembly that is mounted to a pneumatic tire. The invention also related to methods of forming the monitoring device and patch assembly.
2. Background Information
Monitoring the internal conditions of a pneumatic tire while the tire is in use on a vehicle is becoming increasingly desired in the art. One problem with this technology is protecting the relatively sensitive electronic monitoring device in the relatively harsh environment inside a tire. Another problem in the art is that the inner surface of a tire does not have surfaces where monitoring devices may be easily mounted in a secure manner.
Protecting monitoring devices against harsh tire conditions has been accomplished in the past by encapsulating the monitoring device in an encapsulation or potting material. The potting material is poured over the monitoring device and fills the voids around the elements of the monitoring device. The material hardens and forms a protective block having a high modulus of elasticity around the elements of the monitoring device. The monitoring device is protected in this manner from the flexing and shock forces experienced in a pneumatic tire.
Rubber patches are also known in the art to mount monitoring devices to the inner surface of a tire. The potted monitoring device has been connected to the patch with adhesive and the patch was then adhered to the innerliner of the tire. Other methods of mounting monitoring devices inside tires include forming a pocket in the tire and placing the monitoring device in the pocket. Other methods have placed a rubber patch over the top of the monitoring device to hold the monitoring device against the tire sidewall.
One problem with these mounting solutions is the relatively high number of steps required to mount the monitoring device to the tire. Another problem is the number of times the monitoring device must be handled prior to mounting inside the tire. More importantly, the users of the monitoring devices desire stronger connections between the monitoring device and the tire.
Another problem in the art occurs when the antenna is mounted in a different substrate than the monitoring device. In these situations, a connection must be formed between the monitoring device and the antenna. An example of this situation is shown in patent application Ser. No. 09/301,781 filed Apr. 29, 1999, which is owned by the Assignee of the present application. In this situation, a pair of connectors are used to form the direct physical connection between the antenna and the monitoring device. The problem that has occurred is that the adhesive used to bond the monitoring device to the patch is forced around the connectors sometimes flowing into the connectors. The art desires a solution to this problem by providing a method of connecting the encapsulated monitoring device to a patch while not fouling the connectors.